Fasteners are used in the aerospace industry to mechanically unite various structural components of an aircraft. For example, metal panels that form a portion of a skin of an aircraft wing may be joined to other metal parts via bolts or rivets. In aircraft structures, it is often desirable to install rivets in interference, meaning that the rivet diameter after installation is larger than the diameter of the hole that receives it. Interference fit installation of rivets can facilitate aircraft assembly operations and improve joint performance, particularly fatigue performance. As fasteners are intended to enhance the structural strength of an aircraft, it remains desirable to ensure that the act of installing a fastener does not damage underlying structural components of the aircraft. Specifically, too much radial interference at ends of the rivets is undesirable.
The process of upsetting rivets may be further complicated when using the rivet to attach different components together, such as a wing skin of an aircraft and an underlying stringer. In such environments, it may be desirable to control the amount of radial interference the rivets achieve along the axial length of the rivet throughout the hole in which it is installed. Too little radial interference is undesirable at an axial location.